sheffield



(No Model.)

\Wfiwsmx L. T. SHEFFIELD.

ARTIFICIAL DENTURB.

Patented Nov. 16, 1886.

N. PETERS. PhoKmLillwgraphen Waihlnglon, 0.0

UNITED TATES ATENT' ARTIFICIAL IDENTURE.

SPECIFICATION forming part of Letters Patent. No. 352,784, datedNovember 16, 1886.

Application filetl August 12, 1884. Serial No. 140,357. (NO lIlOdGLl Toall whom it may concern.-

Be it known that I, LUOIUS T. SHEFFIELD, a citizen of the United States,residing in the city, county, and State of New York, have inventedcertain new and useful Improvements in the Manufacture of ArtificialDentures, of

which the following is a specification.

vin the ordinary modes of manufacture, from the shrinking of thestructure in the process of securing the teeth in position; and thisobject I effect by applying a brace to hold the teeth and crowns inposition during the time that the structure is heated and cooling, andin removing that portion of the brace which is not embedded in thestructure in the act of securing the teeth in place.

In the drawings, Figure 1 is a perspective view showing the cast of amouth with the supporting crowns and teeth in position and a braceapplied thereto. Fig. 2 is a side view .of a cast, showing a singlesupporting-crown and supporting-tooth and intermediate brace.

The mouth is first prepared to receive the crowns A, which cover the,molar teeth, and

the caps B, which cover the ends of the roots, and the crowns and capsare then applied properly in position upon a cast, I), which constitutesan exact copy of the natural month.

In order to insure the proper position of the crowns and caps uponthecast, I prefer to apply the said crowns and caps to the teeth and rootsin the mouth, and to then take an impression of the mouth, with whichimpression the crowns and caps are removed, andto then form the cast Dby pouring the plastic the cast, but so as to leave exposed those por'tions of the wire adjacent to the teeth and crowns, to which the wire isthen soldered,

thus holding the teeth and crowns rigidly in their relations to eachother. The supporting crowns and bracing-bars are now removed from themodel and placed in position in the mouth, an impression taken, afterwhich the structure is removed from the mouth and another model ofinvestment material formed. The artificial teeth are now secured inproper position in' relation to the'crowns and teeth I upon thebracing-bars and supports extending between the teeth I and the crownsby means of wax or any suitable material. For instance, the supportsare; first soldered to the teeth and crowns, and then theremaining'artificial teeth are soldered or otherwise secured to the saidsupports, after which any portions of the rod J which may be exposed, orwhich have not been embedded'in the solder, are cut away, so that thedenture consists solely of the crowns, the supporting-teeth I, with thebars or bridges between these teeth, and the artificial teeth mountedupon said bridges.

By the preliminary application of the rod J, as described, thesupporting teeth and FFICE.

crowns are held in rigid and unyielding rela I tion to each other, sothat upon the application of heat in soldering thebridges in place orthe teeth to the bridges, and upon the subsequent coolingof the parts,the rod J will act as a brace to prevent the shrinkage of the heatedportions from drawing the supporting crowns and teeth toward each otherand out of 7 position upon their supports, so that when the denture iscompleted the crowns and caps will be in position to fit accurately thenatural teeth and stumps in the mouth.

Heretofore the bridges have been applied and soldered to thecrowns andsupporting- The rod should of course, be of platina or other refractorymaterial. In some instances the ,wire J will constitute a part of thebridge to which the-teeth are soldered, in which case it will benecessary only to cut away the cross portion between the crowns upon theopposite sides of the mouth, the remaining portions being embedded inthe solder which secures the teeth, and forming therewith the bridge.

Although I have referred to a rod as being used as a brace between thesupporting parts of the structure, it will be apparent that a flat plateadapted to be soldered to each of said supports may be used instead ofsaid rod, it being necessary in such case to cut away all that part ofthe brace-plate not embedded in the supporting structure of the denture.

It will be apparent that the form and arrangement of the brace will bevaried to a greater or less extent, according to the arrangementof thesupporting teeth or crowns.

Without limiting myself to the precise construction and arrangement ofparts shown, I claim 1. The within-described improvement in themanufacture of artificial dentures, the same consisting in firstapplying supporting crowns and teeth in proper position upon a cast ofthe mouth; in then connecting the said supporting-crowns to a braceextending partly across the structure from side to side, whereby theyare held rigidly in their positions in relation to each other; infitting the crowns in the 'mouth, and in then applying and securing theartificial teeth to the bridges or supports between said supportingteeth and crowns, substantially as set forth.

2. The improvement in the manufacture of artificial dentures, consistingin connecting together the supports for a denture by means of asupplemental brace, a part of which crosses from side to side, and thenapplying and securing the artificial teeth between the supports, and inthen removing the exposed portions of the brace, substantially asdescribed.

3. In the manufacture of artificial dentures, preparing the roots andapplying the supporting-teeth in position thereon, applying metalliccrowns to the supporting natural teeth, then taking an impression of themouth and removing the crowns and supporting-teeth therewith, thenconnecting the opposite sides of the structure by asupplemental brace,connecting the crowns and supporting-teeth by the usual bridge, and thensecuring the intermediate artifieial teeth between the supporting teethand crowns and removing the exposed portions of the brace, substantiallyas described.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

LUCIUS T. SHEFFIELD.

Witnesses:

GEO. H. Evans; F. L. FREEMAN.

